An active noise control (ANC) system cancels noise. The ANC system monitors noise such as with the use of a microphone and outputs a noise cancelling sound such as with the use of a speaker. The noise cancelling sound is intended to be opposite in phase and same amplitude in comparison with the noise whereby the noise cancelling sound cancels the noise.
An active vibration control (AVC) system cancels vibrations. The AVC system monitors vibrations such as with the use of a vibration sensor and outputs cancelling forces such as with the use of a vibration actuator. The cancelling forces are intended to be opposite in phase and same amplitude in comparison with forces imposed by the vibrations whereby the cancelling forces cancel the vibrations. In sum, the principle of AVC is to create force based on vibration sensor feedback to neutralize the vibration.
An active sound control (ASC) system outputs sound effects to enhance specific spatial and temporal characteristics of a sound as opposed to attempting to cancel the sound. The ASC system outputs the sound effects such as with the use of a speaker.